With the landing gear retracted, the red indicator light will not come on if an open occurs in which wire?

• A. No. 17
• B. No. 7
• C. No. 19
• D. No. 21

Answer: (C)

The red indicator light relies on a complete electrical path in the gear-retracted condition. When the landing gear is retracted, power must flow through a specific wire to reach the red lamp and return to the source. If that wire develops an open, the circuit is broken and the lamp cannot illuminate, even though other parts of the system may be intact. The other wires aren’t in that same path for this condition, so an open elsewhere won’t prevent the red light from coming on. The key idea is that indicator lights need an unbroken path to operate; breaking any link in that path stops the light from lighting.